Environmental impacts of current biofuels
 Andy Hay (rspb-images.com)
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Low greenhouse gas saving
Common first-generation biofuels usually have a well-to-wheel GHG saving of 30-50% compared to fossil fuel. However, a lot of calculations that deliver these values ignored two important factors, which make the stated GHG saving highly uncertain, sometimes even negative.
1) Nitrous oxide (N2O) emission through fertilizer use
N2O is released to the atmosphere through nitrogen fertilizer application and has nearly 300 times the global warming potential of the same mass of CO2. A recent study leaded by Nobel laureate P.J. Crutzen et al. (2008) has shown that common first-generation biofuels crop such as rapeseed requires high amount of fertilizer input, and thus can contribute as much or more to global warming by N2O emission than cooling by fossil fuel savings. For rapeseed biodiesel, the analysis indicates that the global warming by N2O is on average about 1.0-1.7 times larger than the cooling effect due to ‘saved fossil CO2’ emission, excluding the fossil energy input. Though this finding is still being disputed, this study suggests that current GHG saving by biofuels are over optimistic.
2) Emission through indirect land-use change
Carbon stored in undisturbed natural soils and forests could be released if the land is cleared to replace the extra crops needed as a result of increase biofuels use. There are evidences suggesting that the promotion of corn ethanol in the US leads to near doubling soya prices, which in turn driving conversion of rainforest and savannah in Brazil for soya bean cultivation (Laurance, 2007; Morton et al., 2006). A study published in Science by Searchinger et al. (2008) estimated that large biofuel mandates for US corn ethanol would displace food production to other countries, doubling GHG emission over 30 years and increases GHG for 167 years.
A recent review commissioned by the UK Secretary of State for Transport concluded that GHG emission from indirect land use change is a significant factor in determining the overall GHG savings of biofuels, but there is currently no effective way of quantifying the impacts from indirect land use change (Gallagher, 2008).
 Dieter Hoffman (rspb-images.com)
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Indirect land-use change
It takes land to cultivate biofuel feedstocks, and this creates both direct and indirect land-use change that would affect the biodiversity as well as releasing carbon stored on the land.
Even if biofuels crops are not grown on biodiverse land directly, using available cropland to cultivate feedstocks would divert food production to other area, encourage deforestation elsewhere. For example in the EU, domestically produced rapeseed oil are increasingly used for biodiesel production, which leads to a considerable gap in EU food oil supplies, and this has resulted in an increased import of about 2.5 million tons of food oil since 2002, significantly exceeding historic growth rates (Thoenes, 2006). This gap in food oil supplies is filled mainly by palm oil produced in South East Asia. Together with the increasing use for biofuel, such huge demand in palm oil will translate into more deforestation in tropical countries, particularly in Indonesia and Malaysia. There are already 6.5 million hectares of oil-palm plantations across Sumatra and Borneo, and the palm-oil industry is thought to be responsible for at least half of the observed reduction in orang-utan habitat in the decade between 1992 and 2003 (FoE, 2005a). Moreover, crucial habitats for other endangered mammals species, including tigers, tapirs, clouded leopards and dhole, are significantly reduced due to oil palm expansion (Maddox et al., 2007).
Threatening valuable wildlife habitats
Brazilian Cerrado
The Cerrado, located in Brazil’s central highlands, is a particular concern. By 2004, large-scale soya bean and other farming had reduced the size of this unique habitat to 43% of its original size. Around 1% of the remaining Cerrado is lost every year (Butler, 2007); only 2.2% of the Cerrado is legally protected.
The Cerrado is the world’s most wildlife-rich savannah, and listed as a biodiversity hotspots with a high level of endemism by Conservation International . It contains 837 bird species, including the critically endangered Cone-billed Tanager Conothraupis mesoleuca, and nearly 200 species of mammals, with threatened species such as the Giant Anteater, Pampas Cat and Maned Wolf. Together with around 7000 species of plants and hundreds of species of reptiles and freshwater fish (Klink & Machado, 2005), this area is of huge importance for wildlife.
Moreover, the Cerrado soil and vegetation have high levels of stored carbon. If Cerrado is cleared to cultivate soya bean for biodiesel production, it is estimated that it would take 37 years to repay the carbon debt created by the land conversion (Fargione et al. 2008).
European grassland
Due to the recent boom in biofuels, much land under the Common Agricultural Policy set-aside scheme has been turned into maize and rapeseed crops. This has caused further reduction in habitats available for many European farmland birds, such as Little bustard Tetrax tetrax and Red kite Milvus milvus.
Many studies have confirmed the beneficial role of fallow pockets like set-asides on farmland birds (Bracken & Bolger, 2006; Wretenberg et al., 2007) and mammals (Macdonald et al., 2007). Such land is important for birds because it provides food in winter and undisturbed nesting sites in spring. However, the European Commission has decreased the percentage of land dedicated to set-aside to 0% for the 2008 harvest year, and is proposing its complete abolition as part of ‘Heath Check’ of the Common Agricultural Policy. The justification put forward for this decrease has been the high price of cereals, partly driven by the growth in biofuels.
 Michel Laplace-Toulouse (www.africanlatitude.com)
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Wider pollution and water impacts
Large-scale cultivation of food crop often involves heavy use of pesticide, herbicide and fertilizers, and their effects could extend far away from the actual plantations. In Brazil, evidence suggests that wide-spread pesticide use in soya bean farms is threatening the down-stream Pantanal wetland area (WWF, 2003). This area is one of the world’s largest and most important wetlands and provides refuge to hundreds of bird species, including the endangered Hyacinth macaws Anodorhynchus hyacinthinus, Jabiru Jabiru mycteria and some healthy nesting sites for Wood storks Mycteria americana. Pantanal is rich in mammals and reptiles as well, including jaguars, alligators, giant otters, iguanas, anacondas, anteaters and capybaras.
Besides pollutions by runoff, the irrigation need for biofuel crops would impact the surrounding wildlife, particularly on wetland ecosystems. A current example is a large-scale sugarcane plantations development project in the Tana River Delta on the northeast coast of Kenya. Developers are planning to establish 20 000 hectares of sugarcane plantation 30km upstream of the delta, partly for bioethanol production.
The Tana River Delta consists of a series of complex and seasonally flooded habitats, and is an Important Bird Area (IBA: KE022) with more than 345 species of birds including the threatened Basra Reed Warbler Acrocephalus griseldis and Tana River Cisticola Cisticola restrictus. No less than 22 species with internationally important populations have been recorded there, making the delta one of the key sites in Kenya for bird conservation.
The project intends to extract 28 m3/second of water (a third of river water volume during the dry season) from Tana River to irrigate the sugarcane (Mireri et al., 2008). This huge irrigation need will cause severe competition for water resources between the sugar project, other development projects and downstream domestic, livestock, wildlife, fisheries and ecosystem needs, affecting not just wildlife, but local livelihoods as well.
Reference:
Bracken, F. and Bolger, T. (2006) Effects of set-aside management on birds breeding in lowland Ireland. Agriculture Ecosystem & Environment 117 (2-3): 178-184.
Butler, R. (21 August, 2007) Biofuels driving destruction of Brazilian cerrado. Mongabay Press release. http://news.mongabay.com/2007/0821-cerrado.html
Crutzen, P.J., Mosier, A.R., Smith, K.A., and Winiwarter, W. (2008) N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels. Atmos. Chem. Phys., 8: 389-395. Available at: http://www.atmos-chem-phys-discuss.net/7/11191/2007/acpd-7-11191-2007-print.pdf
Fargione, J. et al. (2008) Land clearing and the biofuel carbon debt. Science 29 February 2008 319:1235-1238.
Friends of the Earth (2005a) The oil for ape scandal: How palm oil threatens orang-utan survival.
Klink, C.A. & Machado, R.B. (2005) Conservation of the Brazilian Cerrado. Conservation Biology 19(3): 707-713.
Laurance, W.F. (2007) Switch to corn promotes Amazon deforestation. Science 14 December 2007 318: 1721.
Macdonald, D.W., Tattersall, F.H., Service, K.M., Girbank, L.G. and Feber, R.E. (2007) Mammals, agri-environment schemes and set-aside – what are the putative benefits? Mammal Review 37 (4): 259-277.
Maddox, T., Priatna, D., Gemita, E. & Salampessy, A. (2007) The conservation of tigers and other wildlife in oil palm plantations. Jambi Province, Sumatra, Indonesia. ZSL Conservation Report No. 7. The Zoological Society of London, London.
Mireri, C., Onjala, J., and Oguge, N. (2008) The economic valuation of the proposed Tana Integrated Sugar Project (TISP), Kenya. Report commissioned by Nature Kenya. Available at: http://www.rspb.org.uk/Images/tana_tcm9-188706.pdf
Morton, D.C. et al (2006) Cropland expansion changes deforestation dynamics in the southern Brazilian Amazon. PNAS 103(39): 14637-14641.Searchinger, T. et al (2008) Use of US cropland for biofuels increases greenhouse gases through emission from land use change. Science 29 Feb 2008 319: 1238-1240.
Thoenes, P. (2006) Biofuels and commodity markets – palm oil focus. Paper represented in AgraInforma conference, Brussels, 24-25 October 2006. Available at: http://www.fao.org/es/esc/common/ecg/122/en/full_paper_English.pdf
Wretenberg. J., Lindstrom, A., Svensson, S. and Part, T. (2007) Linking agricultural policies to population trends of Swedish farmland birds in different agricultural regions. Journal of Applied Ecology 44: 933-941
WWF (2003) Oil palm, soybeans & critical habitat loss. A review prepared for the WWF Forest Conversion Initiative.
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